Perovskite solar cells have recently emerged as a new leader in the third-generation of photovoltaics. Additionally, this new technology has the potential for application in several areas, including aerospace. The light-absorbing material in perovskite solar cells is an organometal halide compound with the perovskite structure (ABX3) where various atoms can be combined and interchanged to tune the optoelectronic properties. Typically, the A site is filled by organic, small- molecule cations (e.g. methylammonium and formamdinium) and/or inorganic atoms (e.g. Cs or Rb), the B site is filled by metal atoms (e.g. Pb2+ or Sn2+), and halide anions (e.g. I- and Br+) fill the X site. In this study, I fabricated organic-inorganic (MAPbI3 and Cs0.05(MA0.17FA0.83)Pb(I0.83Br0.17)3 and all-inorganic (CsPbBr3) perovskite solar cells with to improve the efficiency and stability with the goal of studying operation in low-Earth orbit environment. The harsh environment of space requires materials with good thermal stability due to large variations in temperature. The organic-inorganic solar cells are more efficient than all-inorganic, but the organic cation places limitations on the thermal stability of the material. Thus, all-inorganic perovskite solar cells (e.g. CsPbBr3) were fabricated and studied as the best candidates to survive the extreme conditions in low-Earth orbit.